Cryptomatte glitchs

We’re rendering some cinematics out as EXR 4.26 and using the Cryptomatte/Object IDs. I have noticed two issues:

  1. When selecting IDs in AfterEffects random objects are grouped together. Eg, select the ceiling and a chair is also included in that ID.
  2. When you rerender a sequence, the ID identifiers change, making any compositing you have done void.

Anyone else experienced this? I can recreate these issues on different projects over different systems using 4.26